Class 11 Exam  >  Class 11 Questions  >  Heat of neutralisation of a polybasic acid by... Start Learning for Free
Heat of neutralisation of a polybasic acid by a strong base is - 54.8 kcal mol-1? What is basicity of the acid?
    Correct answer is '4'. Can you explain this answer?
    Verified Answer
    Heat of neutralisation of a polybasic acid by a strong base is - 54.8 ...
    For reaction of 1 mole of H+ and one mole of OH-, -13.6 kcal energy is released. As we have energy released = -54.8, 
    Therefore -13.6×nH+ = -54.8
    nH+ = 4
    So, the basicity of acid given here is 4.
    View all questions of this test
    Most Upvoted Answer
    Heat of neutralisation of a polybasic acid by a strong base is - 54.8 ...
    Heat of Neutralisation:

    The heat of neutralisation is defined as the amount of heat evolved when one gram equivalent of an acid is neutralised by a base. It is expressed in calories or joules per mole.

    Polybasic Acid:

    A polybasic acid is an acid that has more than one ionizable hydrogen atom per molecule. It is an acid that can donate more than one proton or hydrogen ion to a base.

    Calculation of Basicity:

    Basicity is defined as the number of replaceable hydrogen atoms in an acid molecule. It is equal to the number of hydroxide ions that are required to neutralize all the acidic hydrogen atoms present in one molecule of an acid.

    The heat of neutralisation of a polybasic acid is given as -54.8 kcal mol-1. This means that one mole of the polybasic acid reacts with one mole of a strong base to release 54.8 kcal of energy.

    To calculate the basicity of the acid, we need to know the number of replaceable hydrogen atoms present in one molecule of the acid. This can be determined by dividing the heat of neutralisation of the acid by the heat of neutralisation of one mole of hydrogen ions (i.e., 57.1 kcal mol-1).

    Basicity = Heat of Neutralisation of Acid / Heat of Neutralisation of H+ ions
    Basicity = -54.8 / -57.1
    Basicity = 0.96

    Since the basicity is less than 1, it means that the acid is not a monobasic acid. Therefore, it must be a polybasic acid. Since the acid has more than one replaceable hydrogen atom, the basicity must be an integer value.

    Thus, the basicity of the acid is 4, which means that the acid has four replaceable hydrogen atoms per molecule.
    Free Test
    Community Answer
    Heat of neutralisation of a polybasic acid by a strong base is - 54.8 ...
    When one mole H+ neutralizes one mole OH- , the heat released is 57.3 kJ.= (57.3/4.18) kCal. (1cal = 4.18J).
    So here, 54.8 kCal heat is released. Thus moles of H+ or OH- neutralized is (54.8×4.18/57.3) = 4 appx. Thus the basicity of the acid is 4.
    Attention Class 11 Students!
    To make sure you are not studying endlessly, EduRev has designed Class 11 study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Class 11.
    Explore Courses for Class 11 exam

    Top Courses for Class 11

    Heat of neutralisation of a polybasic acid by a strong base is - 54.8 kcal mol-1? What is basicity of the acid?Correct answer is '4'. Can you explain this answer?
    Question Description
    Heat of neutralisation of a polybasic acid by a strong base is - 54.8 kcal mol-1? What is basicity of the acid?Correct answer is '4'. Can you explain this answer? for Class 11 2024 is part of Class 11 preparation. The Question and answers have been prepared according to the Class 11 exam syllabus. Information about Heat of neutralisation of a polybasic acid by a strong base is - 54.8 kcal mol-1? What is basicity of the acid?Correct answer is '4'. Can you explain this answer? covers all topics & solutions for Class 11 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Heat of neutralisation of a polybasic acid by a strong base is - 54.8 kcal mol-1? What is basicity of the acid?Correct answer is '4'. Can you explain this answer?.
    Solutions for Heat of neutralisation of a polybasic acid by a strong base is - 54.8 kcal mol-1? What is basicity of the acid?Correct answer is '4'. Can you explain this answer? in English & in Hindi are available as part of our courses for Class 11. Download more important topics, notes, lectures and mock test series for Class 11 Exam by signing up for free.
    Here you can find the meaning of Heat of neutralisation of a polybasic acid by a strong base is - 54.8 kcal mol-1? What is basicity of the acid?Correct answer is '4'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of Heat of neutralisation of a polybasic acid by a strong base is - 54.8 kcal mol-1? What is basicity of the acid?Correct answer is '4'. Can you explain this answer?, a detailed solution for Heat of neutralisation of a polybasic acid by a strong base is - 54.8 kcal mol-1? What is basicity of the acid?Correct answer is '4'. Can you explain this answer? has been provided alongside types of Heat of neutralisation of a polybasic acid by a strong base is - 54.8 kcal mol-1? What is basicity of the acid?Correct answer is '4'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice Heat of neutralisation of a polybasic acid by a strong base is - 54.8 kcal mol-1? What is basicity of the acid?Correct answer is '4'. Can you explain this answer? tests, examples and also practice Class 11 tests.
    Explore Courses for Class 11 exam

    Top Courses for Class 11

    Explore Courses
    Signup for Free!
    Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
    10M+ students study on EduRev